11112211221 has 16 divisors (see below), whose sum is σ = 15252930048. Its totient is φ = 7190769600.

The previous prime is 11112211219. The next prime is 11112211259. The reversal of 11112211221 is 12211221111.

It is a happy number.

11112211221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 11112211221 - 2¹ = 11112211219 is a prime.

11112211221 is a modest number, since divided by 12211221 gives 111 as remainder.

It is a self number, because there is not a number n which added to its sum of digits gives 11112211221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11112211291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 72165 + ... + 165626.

It is an arithmetic number, because the mean of its divisors is an integer number (953308128).

Almost surely, 2^11112211221 is an apocalyptic number.

It is an amenable number.

11112211221 is a deficient number, since it is larger than the sum of its proper divisors (4140718827).

11112211221 is a wasteful number, since it uses less digits than its factorization.

11112211221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 238252.

The product of its digits is 16, while the sum is 15.

Adding to 11112211221 its reverse (12211221111), we get a palindrome (23323432332).

It can be divided in two parts, 111 and 12211221, that multiplied together give a palindrome (1355445531).

The spelling of 11112211221 in words is "eleven billion, one hundred twelve million, two hundred eleven thousand, two hundred twenty-one".